ASP.NET

GMap1.ID = "GMap1";
GMap1.enableServerEvents = true;
GMap1.serverEventsType = GMap.ServerEventsTypeEnum.AspNetPostBack;
//GMap1.MarkerClick += new GMap.GMap_Handler_ServerEvent_MarkerClick(GMap1_MarkerClick);
GMap1.MarkerClick += new GMap.GMap_Handler_ServerEvent_MarkerClick(GMap1_MarkerClick);
GMap1.Click += new GMap.GMap_Handler_ServerEvent_Click(GMap1_Click);
GMap1.enableHookMouseWheelToZoom = true;
Controls.Add(GMap1);
GControl control2 = new GControl(GControl.preBuilt.MapTypeControl, new GControlPosition(GControlPosition.position.Top_Right));
GMap1.addControl(control2);
GMap1.addControl(new GControl(GControl.preBuilt.LargeMapControl));
GMap1.enableHookMouseWheelToZoom = true;
GMap1.enableGKeyboardHandler = true;

private void showEventsOnMap(DataTable dtEvents)
{
    GMarker gm;

    litNoMap.Visible = false;
    GMap1.Visible = true;
    //MarkerManager mManager = new MarkerManager();
    //GMap1.resetMarkerManager();
    GMap1.resetMarkers();

    if (dtEvents.Rows.Count > 0)
    {
        double lat = Convert.ToDouble(dtEvents.Rows[0]["Latitude"]);
        double lng = Convert.ToDouble(dtEvents.Rows[0]["Longitude"]);
        GLatLng latlng = new GLatLng(lat, lng);
        GMap1.setCenter(latlng, 8);
        GLatLngBounds bounds = new GLatLngBounds(latlng, latlng);

        string strHTML = string.Empty;
        string myDate = string.Empty;

        foreach (DataRow dr in dtEvents.Rows)
        {
            gm = new GMarker(new GLatLng(Convert.ToDouble(dr["Latitude"]), Convert.ToDouble(dr["Longitude"])));
            myDate = Convert.ToDateTime(dr["EventDate"].ToString()).ToShortDateString();
            strHTML = dr["City"].ToString() + ":  (" + myDate + ") - " + dr["Summary"].ToString().Replace("\"", "");
            GMarkerOptions go = new GMarkerOptions();
            go.title = strHTML;
            gm.options = go;
            //mManager.Add(gm, 0, 10);
            //mManager.Add(gm, 8);
            bounds.extend(gm.point);
            GMap1.addGMarker(gm);

        }
        //GMap1.markerManager = mManager;

        if (GMap1.getBoundsZoomLevel(bounds) >= 0) //getBoundsZoomLevel function doesn't work consistently!
            GMap1.GZoom = GMap1.getBoundsZoomLevel(bounds);
        GMap1.setCenter(bounds.getCenter());
    }
    string strCSV = (new Utilities()).GetTabDelimited(dtEvents);
    dvGTD.Visible = false;
    litNoMarkerInfo.Visible = false;
}

<asp:dropdownlist id="ddlPackageSelect" visible="true" runat="server" autopostback="true" xmlns:asp="#unknown"></asp:dropdownlist>

private void PopulatePackageDropDown()
		{
			using (StoredProcedure sp = new StoredProcedure("GetPackageDropDown", "celebro"))
			{
				try
				{
					DataSet gh = sp.GetDataSet();

					ddlPackageSelect.DataSource = gh;
					ddlPackageSelect.DataTextField = "Name";
					ddlPackageSelect.DataValueField = "Id";
					ddlPackageSelect.DataBind();


					if (sp.RC == (int)ReturnCode.SUCCESS)
					{
						ddlPackageSelect.Items.Insert(0, new ListItem("All Packages", "0"));
					}
				}
				catch (Exception e)
				{
					lblMessage.Text = e.Message;
				}
			}
		}

private void InitializeComponent()
{			
this.ddlPackageSelect.SelectedIndexChanged += new EventHandler(ddlPackageSelect_SelectedIndexChanged);			
}	

protected void ddlPackageSelect_SelectedIndexChanged(object sender, EventArgs e)
		{
			if (ddlPackageSelect.SelectedIndex == 0)
			{
				BuildGlobalStylesheetList();
			}
			else
			{
				BuildPackageStylesheetList(int.Parse(ddlPackageSelect.SelectedValue.ToString()));
			}
			StylesheetDetail.Visible = false;

		}